Well, they are still the cheapest troop ingame and if you want to kill for example 1000 rowdies then it's the best to use 1000 hobos for that. Sure, you are losing 400,000 alcohol but the defender is losing 600,000 weapons and weapons>alcohol.

I have to do some test battles but atm my gut is telling me that the hobo is the #1 attacker if you want to get rid of these pesky rowdies.